W I N

W I T

( 490 )

eafily into a white opake enamel. It occurs inthe iron mines of Northo in Sweden , and nearArerulahl in Norway .

WETZCHIEFER. See TtiONscHtEFEk.

WHINSTONE. See Basalt and Trap.

WHITE COPPER. See Copper. (Alloysof).

WHITE LEAD, or Cerujfe. See Lead.

WINE.

Under the articles Fermentation, Brandy ,Alcohol and Tartar , we have already defcribed(fufficiently at length for a manufadlure notufed in this country) the method of convertingthe grape juice into wine, and of procuringardent fpirit from the latter by diltillation;we Hull therefore in this place only mentionthe analyfis of wine as given by M. Chaptal inhis elegant and valuable memoirs on the cultureand produce of the vine’.

All wines contain an acid, alcohol, tartar,extradl, aroma, and a colouring matter. Theprefence and nature of each of thefe principlesmay be afcertained in the following way.

r. Acid. All wines, even the fofteft andmildeft, redden litmus, and therefore contain anacid. This abounds however chiefly in thethin wines of wet and cold climates, wdiere thegrape juice or mujl contains but a fmall por-tion of fugar. When wine has been boiled toextract the brandy, the liquor that remains inthe Hill, and is thrown away as ufelefs, is a fournaufeous fluid with an acrid and burnt flavour.When filtered and allowed to remain at reftfor a time, it depofits a good deal of extrac-tive matter, becomes covered with mould, andthen contains a notable quantity of acetousacid, which may be feparated by diltillation.The acid is however not entirely acetous, atleaft: not till after Handing a confiderable time,for it precipitates and forms an infoluble faitwith lime water, and with thv fo'uble falts offilver, lead, and mercury, and appears to be theMalic acid mixed with a little Citric , both ofwhich are converted into vinegar by fpontaneousdecompofition. The wines that contain thegreateft quantity of thefe acids yield the worftbrandy, nor is there any method yet known offeparating or neutralizing the acid, without ma-terially injuring the quality, or leffening thequantity of the ardent fpirit.

1. Alcohol.. The exiftence of this principlear.d mode of extradlion by diltillation has beenfully defcribed under the article Brandy . Thequantity of alcohol varies prodigioufly. Theitrong, rich, full-bodied wines of the wannervine countries will yield as much as a third of

ardent fpirit; whilll the thin light wines willoften give no more than about -j^th of the fameftrength.

3. Tartar. This fubftance has alfo beenfully defcribed in its proper place. Tartar isnot altogether a product of the fermentation ofwine, fince it is contained in mult, though infmall quantity.

4.. Extract. Mull contains an abundance ofextractive matter, which materially allilts thefermentation, and is afterwards found, in partat lealt, in the lees, but another portion may beobtained from the wine by evaporation. It isalfo extract that mixes with and colours thetartar. By age the quantity of extractive mat-ter diminilhes.

Aroma. All wines poffefs a peculiar andgrateful fmell, which would indicate a diilindlaromatic principle, but it has never been exhi-bited in the form of eflential oil, or conderdedin any finalier quantity by diltillation or anyother mode. To give wine all its aroma itIhould be fermented very flowly.

6 - Colouring Matter. The hulk of the redgrape contains a good deal of colour, which isextracted when the entire fruit is prelled, andbecomes diffolved in the wine when the fer-mentation is compleat. Many fubltances willfeparate the colour. ■ If lime-water is added tohigh-coloured wine a precipitate is formed ofmalat of lime that carries down with it all thecolouring matter, which cannot again be fepa-rated either by water or alcohol. But if winealone is evaporated gently to drynefs, and therefidue treated -with alcohol, the colouring mat-ter diffolves therein. W.e may add too, that thenatural colour of wine is entirely and fpeedilydeftroyed by the addition of hot well-burntcharcoal in pretty fine powder. The colour of.red wine in the llate in which we receive it isnot entirely that of the grape, but is given byother colouring fubllances, which however arequite innoxious.

WITHERITE. Barolite, Kirw. Nativecarbmat of barytes.

Its colour is yellowiih-grey, palling into grey-ifii-white and pale wax-yellow. It occurs inmafs, difleminated, and rarely cryllallized. Itsforms are 1. a flattened hexahedral prifm termi-nated by hexahedral pyramids.

2. The lame, with the lateral edges, of theprifin and pyramid truncated.

3. A pyramidal dodecahedron.

The cryltals are in general very fmall, eitherimplanted in the maffive varieties of this mine*

* An, Chun, Tom xxxv, xxxvi, and x-xxvii,